Skid-Steer Rock Saw

Drive Train Modification

Team Members

Kelly Hogue Kristen Tucker

Matthew Gassen Buck Melton

by

Prepared for CONEQTEC Universal and Senior Design - BAE 4022

Project Sponsor

• CONEQTEC Universal

• Skid steer attachment manufacturer

• President Gary Cochran

Mission Statement

• Blue Diamond Machinery strives to

improve products by implementing high

quality designs, increasing efficiency, and

surpassing the demands of our clients.

Production Model

• Cutting depth is less

than the wheel radius

• To increase depth of

cut, the diameter of

the blade must

increase, therefore,

increasing the overall

dimensions and

weight of the

attachmentProvided by CONEQTEC

Patent Search

• Slashing Loader – Ring & Pinion Gears

• Tree Harvester – Saw Blade

• Power Saw – Gears, Blade

• Concrete Saw – Debris Removal

CONEQTEC Rock Saw Prototype

Provided by Coneqtec

Features of CONEQTEC Prototype

• Depth of cut > wheel radius

– 18 inches deep, 2.5 inches wide

• Powered by hi-flow hydraulic system

– 89 hhp input to attachment

• Attachment is laterally adjustable

Hydraulic System Specifications

Hydraulic Power Kits A B C

Flow (gpm) 34 40 33

Pressure (psi) 4500 3200 4060

Power (hhp) 89 75 78

Hydraulic Motor

Displacement (cc) 200 200 200

RPM 320 380 310

Torque (ft lbs) 730 520 660

Total Force (lbs) 450 320 410

Uses

• More versatile than a trencher

• Cut anything other than reinforced

concrete

• Install fiber optics, plumbing, etc…. Under

existing roadways/sidewalks

• Install cement curbs on asphalt roadways

CONEQTEC Prototype

Demonstration

Problem Statement

• Increase cutting depth to greater than

blade radius

• Modify CONEQTEC prototype to

increase useful life

• Prevent hydraulic motors from running in

debris piles

Statement of Work

• Increase useful life of the saw from less than

50 hrs to over 100 hrs.

• Current limiting factor is the high rate of wear

on the ring gear teeth.

Statement of Work:

Gear Mesh

Redesign gear mesh

• Initial design

– Protruding ring gear

teeth mesh with

cylindrical pinion gear

teeth.

• Alternative design

– Acme pinion gears

mesh into ring gear

holes.

Gear Mesh Calculator

• Used to calculate

gear sizes, gear

ratios, and gear hole

spacing

• Three independent

variables chosen by

user

• Warning/Approval

messages indicate if

gear hole spacing is

sufficient

Gear Specifications

• 2 Gears – 7 teeth

• 3/4” thick steel

• 1/4” spacing between gears

• Top Gear– Dedendum circle diameter

(D): 6.16”

– Addendum circle diameter (A): 8.08”

• Bottom Gear– Dedendum circle diameter

(D): 5.76”

– Addendum circle diameter (A): 7.62”

D

A

Wheel and Gear Specifications

Hydraulic Power Kits A B C

Cutting Wheel

RPM 75 88 73

Torque (ft lbs) 3100 2200 2800

Force (lbs) 8300 5900 7500

Ring Gear Holes

Shear Force (psi) 1000 720 910

Pinion Gear

Shear Force (psi) 300 220 270

Fatigue Load (psi) 41,000

Ring Gear Evolution

CONEQTEC PROTOTYPE BDM PROTOTYPE

BDM PROTOTYPE INSERT PROGRESSION

Final Ring Gear Design

• Gear holes cut into the

wheel

• Inserts used to prevent

wear on gear holes

– Bar Stock: 3/4” x 3”

– Key Stock: 1/4” x 3/4” x 3”

– Retainer plates – 3/8” thick

– Bolted on one side

– Welded on opposite side

– Flat head socket cap screws

3/8” x 3/4”

BDM Gear Mesh Demonstration

Statement of Work: Motors

• Prevent hydraulic motors from running in

debris

Motor Repositioning

Rotate motors into a vertical position

by mounting above the wheel.

CONEQTEC Prototype BDM Prototype

BDM Rock Saw Prototype

Fully Descended Fully Recessed

Budget

Materials $1,623

Fasteners $112

Tools $36

Total $1,772

Recommendations

• Replace gear shafts by using hydraulic motors with wheel mount flange

• Make motors vertically and laterally adjustable to allow for gear adjustability

• Attach a front debris flap for added safety

• Holes could be added to outer frame to reduce weight and increase ease of maintenance

Recognitions

• Gary Cochran – CONEQTEC Universal

• Dennis Skraba – CONEQTEC Universal

• Dr. Paul Weckler – OSU BAE Senior Design Professor and Advisor

• Wayne Kiner – OSU BAE Laboratory Manager

• Bobby Flores, Robert Harrington,

and Robert Harshman – OSU BAE Laboratory

• Stillwater Steel – Fabrication

• Steve Miller – Interstate Tool – Fabrication

• Railroad Yard – Fabrication

Questions?